1. Field of the Invention PA1 storing a position of the center of the card mounting portion on absolute coordinates and relative positions of the probes on the probe card in a memory of a controller; PA1 mounting the probe card to the card mounting portion, setting one of the probes of the probe card as a reference probe, detecting a position of the reference probe on the absolute coordinates, and inputting the detected position in the controller; PA1 calculating a relative position of the probe arrangement center relative to the reference probe by the controller by referring to the relative positions of the probes stored in the memory; PA1 calculating a position of the probe arrangement center on the absolute coordinates by the controller based on the position of the reference probe on the absolute coordinates and the relative position of the probe arrangement center; and PA1 calculating a positional error of the position of the probe arrangement center with respect to the position of the center of the card mounting portion on the absolute coordinates by the controller, and identifying the positions of the probes on the absolute coordinates based on the calculated positional error. PA1 According to a second aspect of the present invention, there is provided, in a prober comprising a probe card having a plurality of probes, and a card mounting portion for mounting the probe card, a method of identifying, after mounting the probe card on the card mounting portion, positions of the probes, comprising the steps of: PA1 storing relative positions of the probes on the probe card in a memory of a controller; PA1 mounting a dummy card having a shape congruent with that of the probe card on the card mounting portion, detecting an imaginary center of the dummy card on absolute coordinates, and inputting the detected imaginary center in the controller, the imaginary center being arranged to correspond to a probe arrangement center of the probe card; PA1 mounting the probe card to the card mounting portion, setting one of the probes of the probe card as a reference probe, detecting a position of the reference probe on the absolute coordinates, and inputting the detected position in the controller; PA1 calculating a relative position of the probe arrangement center relative to the reference probe by the controller by referring to the relative positions of the probes stored in the memory; PA1 calculating a position of the probe arrangement center on the absolute coordinates by the controller based on the position of the reference probe on the absolute coordinates and the relative position of the probe arrangement center; and PA1 calculating a positional error of the position of the probe arrangement center with respect to the position of the imaginary center of the dummy card on the absolute coordinates by the controller, and identifying the positions of the probes on the absolute coordinates based on the calculated positional error. PA1 A probing method according to the present invention that employs the probe position identifying methods according to the first and second aspects further comprises the steps of: PA1 placing a test target on a work table of the prober; PA1 driving the work table through the controller by referring to the positions of the probes on the absolute coordinates, and bringing the probes into contact with the test target; and PA1 sending a test signal from a tester of the prober to the test target through the probes, and measuring electrical characteristics of the test target by the tester in accordance with a response signal sent back from the test target. PA1 According to the present invention, identification of the probe positions of the probe card can be performed easily, thus increasing the efficiency of the operation. Especially, even when the contact between the electrode pads on the wafer and the probes is difficult to observe, as in a probe card having probes of a vertical type, alignment of the electrode pads and the probes can be easily performed.
The present invention relates to a method of identifying a probe position and a probing method in a prober for a substrate to be examined, e.g., a semiconductor wafer.
2. Description of the Related Art
In the semiconductor device manufacturing process, a large number of semiconductor devices are formed as chips on a semiconductor wafer. Then, the wafer is cut into the chips, i.e., the semiconductor devices in a die cut step. In the semiconductor device manufacturing process, before the wafer is cut, the electrical characteristics of the semi-completed semiconductor devices are tested and determined by using a prober. Only the semiconductor devices that are determined as non-defective articles as the result of test measurement are sent to the subsequent steps, e.g., packaging.
The prober has a wafer work table which is made to be movable in the X, Y, Z, and .theta. directions. A probe card having a large number of probes corresponding to the electrode pads of a semiconductor device is fixed above the work table with an appropriate holding tool. For measurement, a test target, e.g., a wafer, is placed and held on the work table. The work table is driven, the probes are brought into contact with the electrode pads of the semiconductor device, and test measurement is performed by a tester through the probes.
In order to accurately bring the probes of the prober into electrical contact with the electrode pads of the semiconductor device, the distal ends of the probes must be correctly guided to the electrode pads of the semiconductor device and aligned with them. Conventionally, a specific semiconductor device on the wafer is moved to under the probe card by moving the stage. Then, the distal ends of the probes are recognized by utilizing, e.g, a camera, and manually aligned with the electrode pads of the semiconductor device. In this method, the operator must be specially trained, and the aligning operation becomes very cumbersome. When a probe card, e.g., a probe card having probes of a so-called vertical type, that visually conceals contact between the probes and the electrode pads is used, visual observation for the purpose of alignment is difficult, sometimes making it difficult to perform accurate operation.